Treatment of skins and hides for the removal of fat, &amp;c.



F. H. E. LEHMANN.

TREATMENT OF SKINS AND HIDES FOB. THE REMOVAL OF FAT, &c.

APPLIGATI'ON FILED MAR. 21, 1909v 1,048,709. Patented Dec. 31, 1912.

Quorum:

UNITED sra'rns PATENT orator].

FRIEDRICH HEINRICH EDUARD LEHMANN, 0F EILENBURG, GERMANY."

TREATMENT OIKSKINS AND HIDES FOR THE REMOVAL OF FAT, 860.

1,048,709. specimen armors t nt. Patented Dec. 31, 1912.

. M} v 4 '1 Application filed March 27, 1,909. Serial No. 488,130.

To all whom it may concern: represents cathode plates. i a i Be it-known that I, FRIEDRICH I'IEINRICH EDUARD LmnuANN, a subject of the German Emperor, residing at Eilenburg, in the Province-of Saxony, in Germany, have in vented certain new and useful improvements in the treatment of skins and hides for the removal of fat, grease, oil and lime and for disinfecting purposes, of which the following is a specification.

Fatty and oily substances have hitherto commonly been removed from the hides and skins of animals by extracting them, accord- .ing, to the principle of lixiviation or substitution, by means of solvents of fat and oil, for example, benzin, bisultid of carbon, or tetra -chlorid of carbon, or by saponilication and washing, or by absorption of tat-absorbing earths. Usually the skins and the hairs or feathers are treated separately in this manner; more rarely the skin treated together with the hair or feathers. 1

The present invention consists in a process in which skins with haizwand feathers are treated by passing an electric current ,through them in baths ot a nature dcpcmling on the kind of skin to be treated, for example the skins of horses, oxen, cows, calves. sheep,'wild animals or birds. This process saponities the fatty and oily matters and also removes them from the skin and it removes from the skin all substances for example lime of which it. must be deprived for the purpose of further treatment and preservation, the removal being ctl'ected in a manner which has no deleterious cll'ect on the quality and peculiarity of the skin, and by which the subsequent treatment is simplified and cheapened.

The process is distinguished from the known processes of electrically treating loose Wool and fibrous material by the fact that the fiber, hair, feathers and down are still attached to the skin and are treated together with the latter.

The invention is illustrated in the annexed drawing in which- Figure l is a diagrammatic section illustrating skins suspcmlod in a bath between electrodes which are alternately anode and cathode. Figs. 2 and I} are similar sections of apparatus in which the skins may be caused to travel through the bath horizontally or obliquely respectively.

1 represents the vat containing the bath.

2 represents skins.

at represents anode plates. 1 In Fig. 2, 30 represents a traveling band passing about pulleys 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, and 40 represents another traveling band passing about plllle' \'s.6,,8, 10, 12,14, 16, 18. t

In Fig. 3, the band 30 .passes'about i 250, 270, 290, 310, 330, 350, and the band 40 passes about pulleys 60, S0, 100, 120, 140, 160, 180, 200, 220, 240, 260, 280.

The bands may travelalternately in the direction of the arrows I and ll.

37, 89, 4-1, 43 represent squeezing rollers.

The skins to be treated may be placed in .an electrolytic bath, provided with a membrane or diaphragm, or they may he placed between the electrodes, in any desired position, so that they themselves form diaphragms during the intermittent or conlinw ous action ol. the elcctric current. The skins may remain stationarily suspended during the, process or may be moved. Unless the bath acquires alkaline properties by tho intrmluction ol" the skins tlunnselvcs, alkalis must be spe ially added thereto. (.urrcnls o'l' from 150 to 250 ampcres are preferably used varying, with the size and condition of the hide, at pressures of from 3 lo 15 volts, according to the density o l' the growth oi? hair.

The nature and strength of the bath. as well as the density and pressure of lbc'cnrrent uscd l'or separating the limo. dcpcnd on the kind of skin. hair or wool to be treated. inasmuch as the separation ol the lime takes place very rapidly, a considerable saving of time is cll'cct'cd by thc clcclrolytic process and the loss of fiber-material is much less than in the case ol' the washing proctsses hitherto adopted. 'llnlina: may be used again.

Sin'mllanconsly with the removal of fat by the process dcscrilwd, the skins may undergo a. disinfecting process. The chlorids contained in the fibers, ctr... not themselves as disinfectants, and suitable disinl'cctants, for example formic aldehyde and compounds thercol, may be added to the baths. After the clcctrolyiic pr cess, the skins. hairs, c1c., may, if desired. be treated in a bath containing formic aldehyde or compounds thereof, or solutions of l'ormic aldclrvde or its cmnpoumls may be poured over the skins, on the one hand as a reliable safeguard against the danger of anthrax,

and on the other hand for the purpose of impartingto'the skin qualities which faciliv.t'ate and assist subsequent operations of 'tosecure purpose firstly of saponifyingsaid fat,

grease or oil and secondly of driving the same out of the skins and hides. a

2. The method of treating skins and hides of animals of all kinds for the removal of fat, grease and oil, comprising passing electric currents through them in alkaline baths,

containing disinfectants, said bathscontaining no lime.

3. T e process of treating skins and hides of animals of allkinds for the removal of' fat, grease and oil, comprislng subjecting them to the passage of electric currents in alkaline baths and subsequently treating said skins with formic aldehyde or its oompounds, for the purposes set forth.

In. Witness-whereof I have signed this specification in the presence of two Witnesses.

FRIEDRICH HEINRICH EDUARD LEHMANN. 'Witnesses:

HERM. SACK, RUDULPHV FRICKE. 

